/* Copyright 2009
 *
 * This program and the accompanying materials
 * are made available under the terms of the
 * Eclipse Public License v1.0 which accompanies
 * this distribution, and is available at
 *
 * 		http://www.eclipse.org/legal/epl-v10.html
 *
 * Unless required by applicable law or agreed to in
 * writing, software distributed under the License is
 * distributed on an "AS IS" BASIS, WITHOUT WARRANTIES
 * OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * Contributors:
 * 	   IBM Corporation - initial API and implementation for JDT/DLTK
 *     Sean W. Quinn - initial adoption for use with PHP from various sources.
 */
package org.eclipse.php.internal.core.util;

import org.eclipse.php.core.util.IConstantPool;
import org.eclipse.php.core.util.IConstantPoolConstant;
import org.eclipse.php.core.util.IConstantPoolEntry;
import org.eclipse.php.core.util.IScriptFileAttribute;
import org.eclipse.php.core.util.ScriptFormatException;

/**
 * Default implementation of IScriptFileAttribute
 */
public class ScriptFileAttribute extends ScriptFileStruct implements IScriptFileAttribute {
	public static final IScriptFileAttribute[] NO_ATTRIBUTES = new IScriptFileAttribute[0];
	private long attributeLength;
	private int attributeNameIndex;
	private char[] attributeName;

	public ScriptFileAttribute(byte[] scriptFileBytes, IConstantPool constantPool, int offset)
			throws ScriptFormatException {
		this.attributeNameIndex = u2At(scriptFileBytes, 0, offset);
		this.attributeLength = u4At(scriptFileBytes, 2, offset);
		IConstantPoolEntry constantPoolEntry = constantPool.decodeEntry(this.attributeNameIndex);
		if (constantPoolEntry.getKind() != IConstantPoolConstant.CONSTANT_Utf8) {
			throw new ScriptFormatException(ScriptFormatException.INVALID_CONSTANT_POOL_ENTRY);
		}
		this.attributeName = constantPoolEntry.getUtf8Value();
	}

	public int getAttributeNameIndex() {
		return this.attributeNameIndex;
	}

	/**
	 * @see IScriptFileAttribute#getAttributeName()
	 */
	public char[] getAttributeName() {
		return this.attributeName;
	}

	/**
	 * @see IScriptFileAttribute#getAttributeLength()
	 */
	public long getAttributeLength() {
		return this.attributeLength;
	}

}
